The patch titled
Subject: mm: convert wp_page_copy() to use folios
has been added to the -mm mm-unstable branch. Its filename is
mm-convert-wp_page_copy-to-use-folios.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-convert-wp_page_copy-to-use-folios.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: convert wp_page_copy() to use folios
Date: Mon, 16 Jan 2023 19:18:11 +0000
Use new_folio instead of new_page throughout, because we allocated it
and know it's an order-0 folio. Most old_page uses become old_folio,
but use vmf->page where we need the precise page.
Link: https://lkml.kernel.org/r/20230116191813.2145215-4-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/mm/memory.c~mm-convert-wp_page_copy-to-use-folios
+++ a/mm/memory.c
@@ -3043,8 +3043,8 @@ static vm_fault_t wp_page_copy(struct vm
const bool unshare = vmf->flags & FAULT_FLAG_UNSHARE;
struct vm_area_struct *vma = vmf->vma;
struct mm_struct *mm = vma->vm_mm;
- struct page *old_page = vmf->page;
- struct page *new_page = NULL;
+ struct folio *old_folio = NULL;
+ struct folio *new_folio = NULL;
pte_t entry;
int page_copied = 0;
struct mmu_notifier_range range;
@@ -3052,23 +3052,22 @@ static vm_fault_t wp_page_copy(struct vm
delayacct_wpcopy_start();
+ if (vmf->page)
+ old_folio = page_folio(vmf->page);
if (unlikely(anon_vma_prepare(vma)))
goto oom;
if (is_zero_pfn(pte_pfn(vmf->orig_pte))) {
- struct folio *new_folio;
-
new_folio = vma_alloc_zeroed_movable_folio(vma, vmf->address);
if (!new_folio)
goto oom;
- new_page = &new_folio->page;
} else {
- new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma,
- vmf->address);
- if (!new_page)
+ new_folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, vma,
+ vmf->address, false);
+ if (!new_folio)
goto oom;
- ret = __wp_page_copy_user(new_page, old_page, vmf);
+ ret = __wp_page_copy_user(&new_folio->page, vmf->page, vmf);
if (ret) {
/*
* COW failed, if the fault was solved by other,
@@ -3077,21 +3076,21 @@ static vm_fault_t wp_page_copy(struct vm
* from the second attempt.
* The -EHWPOISON case will not be retried.
*/
- put_page(new_page);
- if (old_page)
- put_page(old_page);
+ folio_put(new_folio);
+ if (old_folio)
+ folio_put(old_folio);
delayacct_wpcopy_end();
return ret == -EHWPOISON ? VM_FAULT_HWPOISON : 0;
}
- kmsan_copy_page_meta(new_page, old_page);
+ kmsan_copy_page_meta(&new_folio->page, vmf->page);
}
- if (mem_cgroup_charge(page_folio(new_page), mm, GFP_KERNEL))
+ if (mem_cgroup_charge(new_folio, mm, GFP_KERNEL))
goto oom_free_new;
- cgroup_throttle_swaprate(new_page, GFP_KERNEL);
+ cgroup_throttle_swaprate(&new_folio->page, GFP_KERNEL);
- __SetPageUptodate(new_page);
+ __folio_mark_uptodate(new_folio);
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm,
vmf->address & PAGE_MASK,
@@ -3103,16 +3102,16 @@ static vm_fault_t wp_page_copy(struct vm
*/
vmf->pte = pte_offset_map_lock(mm, vmf->pmd, vmf->address, &vmf->ptl);
if (likely(pte_same(*vmf->pte, vmf->orig_pte))) {
- if (old_page) {
- if (!PageAnon(old_page)) {
- dec_mm_counter(mm, mm_counter_file(old_page));
+ if (old_folio) {
+ if (!folio_test_anon(old_folio)) {
+ dec_mm_counter(mm, mm_counter_file(&old_folio->page));
inc_mm_counter(mm, MM_ANONPAGES);
}
} else {
inc_mm_counter(mm, MM_ANONPAGES);
}
flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte));
- entry = mk_pte(new_page, vma->vm_page_prot);
+ entry = mk_pte(&new_folio->page, vma->vm_page_prot);
entry = pte_sw_mkyoung(entry);
if (unlikely(unshare)) {
if (pte_soft_dirty(vmf->orig_pte))
@@ -3131,8 +3130,8 @@ static vm_fault_t wp_page_copy(struct vm
* some TLBs while the old PTE remains in others.
*/
ptep_clear_flush_notify(vma, vmf->address, vmf->pte);
- page_add_new_anon_rmap(new_page, vma, vmf->address);
- lru_cache_add_inactive_or_unevictable(new_page, vma);
+ folio_add_new_anon_rmap(new_folio, vma, vmf->address);
+ folio_add_lru_vma(new_folio, vma);
/*
* We call the notify macro here because, when using secondary
* mmu page tables (such as kvm shadow page tables), we want the
@@ -3141,7 +3140,7 @@ static vm_fault_t wp_page_copy(struct vm
BUG_ON(unshare && pte_write(entry));
set_pte_at_notify(mm, vmf->address, vmf->pte, entry);
update_mmu_cache(vma, vmf->address, vmf->pte);
- if (old_page) {
+ if (old_folio) {
/*
* Only after switching the pte to the new page may
* we remove the mapcount here. Otherwise another
@@ -3164,18 +3163,18 @@ static vm_fault_t wp_page_copy(struct vm
* mapcount is visible. So transitively, TLBs to
* old page will be flushed before it can be reused.
*/
- page_remove_rmap(old_page, vma, false);
+ page_remove_rmap(vmf->page, vma, false);
}
/* Free the old page.. */
- new_page = old_page;
+ new_folio = old_folio;
page_copied = 1;
} else {
update_mmu_tlb(vma, vmf->address, vmf->pte);
}
- if (new_page)
- put_page(new_page);
+ if (new_folio)
+ folio_put(new_folio);
pte_unmap_unlock(vmf->pte, vmf->ptl);
/*
@@ -3183,19 +3182,19 @@ static vm_fault_t wp_page_copy(struct vm
* the above ptep_clear_flush_notify() did already call it.
*/
mmu_notifier_invalidate_range_only_end(&range);
- if (old_page) {
+ if (old_folio) {
if (page_copied)
- free_swap_cache(old_page);
- put_page(old_page);
+ free_swap_cache(&old_folio->page);
+ folio_put(old_folio);
}
delayacct_wpcopy_end();
return 0;
oom_free_new:
- put_page(new_page);
+ folio_put(new_folio);
oom:
- if (old_page)
- put_page(old_page);
+ if (old_folio)
+ folio_put(old_folio);
delayacct_wpcopy_end();
return VM_FAULT_OOM;
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
buffer-add-b_folio-as-an-alias-of-b_page.patch
buffer-replace-obvious-uses-of-b_page-with-b_folio.patch
buffer-use-b_folio-in-touch_buffer.patch
buffer-use-b_folio-in-end_buffer_async_read.patch
buffer-use-b_folio-in-end_buffer_async_write.patch
page_io-remove-buffer_head-include.patch
buffer-use-b_folio-in-mark_buffer_dirty.patch
gfs2-replace-obvious-uses-of-b_page-with-b_folio.patch
jbd2-replace-obvious-uses-of-b_page-with-b_folio.patch
nilfs2-replace-obvious-uses-of-b_page-with-b_folio.patch
reiserfs-replace-obvious-uses-of-b_page-with-b_folio.patch
mpage-use-b_folio-in-do_mpage_readpage.patch
mm-memcg-add-folio_memcg_check.patch
mm-remove-folio_pincount_ptr-and-head_compound_pincount.patch
mm-convert-head_subpages_mapcount-into-folio_nr_pages_mapped.patch
doc-clarify-refcount-section-by-referring-to-folios-pages.patch
mm-convert-total_compound_mapcount-to-folio_total_mapcount.patch
mm-convert-page_remove_rmap-to-use-a-folio-internally.patch
mm-convert-page_add_anon_rmap-to-use-a-folio-internally.patch
mm-convert-page_add_file_rmap-to-use-a-folio-internally.patch
mm-add-folio_add_new_anon_rmap.patch
mm-add-folio_add_new_anon_rmap-fix-2.patch
page_alloc-use-folio-fields-directly.patch
mm-use-a-folio-in-hugepage_add_anon_rmap-and-hugepage_add_new_anon_rmap.patch
mm-use-entire_mapcount-in-__page_dup_rmap.patch
mm-debug-remove-call-to-head_compound_mapcount.patch
hugetlb-remove-uses-of-folio_mapcount_ptr.patch
mm-convert-page_mapcount-to-use-folio_entire_mapcount.patch
mm-remove-head_compound_mapcount-and-_ptr-functions.patch
mm-reimplement-compound_order.patch
mm-reimplement-compound_nr.patch
mm-reimplement-compound_nr-fix.patch
mm-convert-set_compound_page_dtor-and-set_compound_order-to-folios.patch
mm-convert-is_transparent_hugepage-to-use-a-folio.patch
mm-convert-destroy_large_folio-to-use-folio_dtor.patch
hugetlb-remove-uses-of-compound_dtor-and-compound_nr.patch
mm-remove-first-tail-page-members-from-struct-page.patch
doc-correct-struct-folio-kernel-doc.patch
mm-move-page-deferred_list-to-folio-_deferred_list.patch
mm-huge_memory-remove-page_deferred_list.patch
mm-huge_memory-convert-get_deferred_split_queue-to-take-a-folio.patch
mm-convert-deferred_split_huge_page-to-deferred_split_folio.patch
shmem-convert-shmem_write_end-to-use-a-folio.patch
mm-add-vma_alloc_zeroed_movable_folio.patch
mm-convert-do_anonymous_page-to-use-a-folio.patch
mm-convert-wp_page_copy-to-use-folios.patch
mm-use-a-folio-in-copy_pte_range.patch
mm-use-a-folio-in-copy_present_pte.patch
mm-fs-convert-inode_attach_wb-to-take-a-folio.patch
mm-convert-mem_cgroup_css_from_page-to-mem_cgroup_css_from_folio.patch
mm-remove-page_evictable.patch
mm-remove-mlock_vma_page.patch
mm-remove-munlock_vma_page.patch
mm-clean-up-mlock_page-munlock_page-references-in-comments.patch
rmap-add-folio-parameter-to-__page_set_anon_rmap.patch
filemap-convert-filemap_map_pmd-to-take-a-folio.patch
filemap-convert-filemap_range_has_page-to-use-a-folio.patch
readahead-convert-readahead_expand-to-use-a-folio.patch
